How many meters can an electromagnetic wave jammer jam

5 to 12 meters or so. The jamming range of an electromagnetic wave jammer depends on a variety of factors, including the type of jammer, power, frequency, antenna gain, etc. The jamming range of a small, low-power electromagnetic wave jammer may be only a few meters to a dozen meters, while the jamming range of a large, high-powered electromagnetic wave jammer may be hundreds of meters, or even farther. An electromagnetic wave jammer is a device used to transmit wireless signals to interfere with or block electrical or communication signals in other wireless devices or systems.